This program-project grant will continue to support studies in differentiation and cancer. Further characterization of the transformation protein encoded in the sarc region of the Rous genome will be undertaken and represents the molecular genetics part of the program in differentiation and neoplasia. Studies on effects of DNA tumor virus on differentiation will be continued utilizing SV40 and embryonal carcinoma cells. Characterization of differentiation-specific membrane proteins of neural tumors will be continued with attempts to extrapolate the studies to normal systems. Chromosomal packaging in human leukemic cells will be studied. Studies of lipophages as a means of incorporating information molecules into cells will be carried out, as will further studies of lectin-binding of tumor cells. Molecular studies of glyco-like foreign molecules of L-cells and studies directing the differentiation of embryonal carcinoma cells will be continued.